The invention relates to an arrangement for pneumatic false-twist spinning, having means for feeding a drawn sliver, having an intake nozzle, having a false-twist nozzle and having means for withdrawing a spun yarn, in which case means for the discharge of the outgoing air of the intake nozzle are provided between the intake nozzle and the false-twist nozzle.
In the case of a known arrangement described in German Patent (DE-PS) No. 27 27 091, the intake nozzle that is developed as a false-twist nozzle, and the false-twist nozzle that follows are arranged at a distance from one another. They are arranged inside a joint housing, at which, behind the intake nozzle as well as behind the false-twist nozzle, suction lines are connected. This has the purpose of removing occurring blown-off fuzz. In the case of this arrangement, there is the danger that between the intake nozzle and the false-twist nozzle, not only blown-off fuzz is sucked off, but also useful fibers that would then be lost to the spinning process. This results in count fluctuations of the spun yarn. This danger would be particularly high when the intake nozzle exercises no or only a slight twisting effect on the sliver and essentially is used only for a loosening-up of the sliver and a forcing-apart of the fiber ends that, in the false-twist nozzle that follows, are then wound around the sliver.
An arrangement is also known (EP-A No. 121 602) in which only one false-twist nozzle is provided, the conical inlet area of which is to have the effect of an intake nozzle. In the case of this construction, an enlarged expansion space exists between the tapering inlet area and the false-twist nozzle, an air intake means being connected to said expansion space. In order to prevent that fiber deposits occur in this expansion space, it is also provided that this annulus is acted upon by scavenging air that, if necessary, is supplied in the form of compressed air.
An object of the invention is to provide an arrangement of the initially mentioned type in which the intake nozzle can serve essentially as a means for the loosening-up and processing of the sliver, without the danger that fiber losses occur by means of the discharge of the outgoing air of the intake nozzle. This objective is achieved according to the invention by the fact that air guiding means are connected to the intake nozzle that discharge the outgoing air of the intake nozzle that is first directed toward the false-twist nozzle, with at least one flow component that is opposed to the transport direction of the sliver.
In the case of this development, the fact is utilized that the sliver and also possibly loose fibers do not follow an abrupt turning-around of the outgoing air of the intake nozzle so that the sliver and also loose fibers reach the false-twist nozzle securely, while, on the other hand, the outgoing air of the intake nozzle is discharged in such a way that it does not interfere with the operation and the air management of the false-twist nozzle that follows.
Other objects, advantages and novel features of the present invention will become apparent from the following detailed description of the invention when considered in conjunction with the accompanying drawings.